CN115433415A - Preparation method of heat-conducting PVC (polyvinyl chloride) - Google Patents

Preparation method of heat-conducting PVC (polyvinyl chloride) Download PDF

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CN115433415A
CN115433415A CN202210987518.3A CN202210987518A CN115433415A CN 115433415 A CN115433415 A CN 115433415A CN 202210987518 A CN202210987518 A CN 202210987518A CN 115433415 A CN115433415 A CN 115433415A
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pvc
heat
conducting
filler
preparing
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CN115433415B (en
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冯继凡
楚振华
李进
张露露
邵帅
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Graphene Polymer Composites R&d Center Shandong Lutai Holding Group Co ltd
Shandong Lutai Holding Group Co Ltd
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Graphene Polymer Composites R&d Center Shandong Lutai Holding Group Co ltd
Shandong Lutai Holding Group Co Ltd
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    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08KUse of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K9/00Use of pretreated ingredients
    • C08K9/08Ingredients agglomerated by treatment with a binding agent
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08JWORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J3/00Processes of treating or compounding macromolecular substances
    • C08J3/12Powdering or granulating
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08KUse of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00Use of inorganic substances as compounding ingredients
    • C08K3/02Elements
    • C08K3/04Carbon
    • C08K3/042Graphene or derivatives, e.g. graphene oxides
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08KUse of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00Use of inorganic substances as compounding ingredients
    • C08K3/38Boron-containing compounds
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08JWORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2327/00Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers
    • C08J2327/02Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers not modified by chemical after-treatment
    • C08J2327/04Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers not modified by chemical after-treatment containing chlorine atoms
    • C08J2327/06Homopolymers or copolymers of vinyl chloride
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08KUse of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00Use of inorganic substances as compounding ingredients
    • C08K3/38Boron-containing compounds
    • C08K2003/382Boron-containing compounds and nitrogen
    • C08K2003/385Binary compounds of nitrogen with boron

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  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Processes Of Treating Macromolecular Substances (AREA)
  • Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)

Abstract

The invention relates to the technical field of heat-conducting high polymer materials, in particular to a preparation method of heat-conducting PVC, which comprises the following steps: (1) Adding a heat stabilizer and a plasticizer into a PVC raw material to prepare gelatinized PVC particles; (2) Carrying out surface treatment on the heat-conducting filler by using a dispersing agent to obtain an active filler; (3) Adding the active filler into the gelatinized PVC particles, and uniformly dispersing at 90-110 ℃ to obtain functionalized PVC powder coated with the active flaky filler on the surface; (4) And (3) putting the functionalized PVC powder into a mold, and performing hot press molding. The heat-conducting PVC prepared by the method has the advantages that the heat-conducting filler is uniformly coated on the surface of PVC particles, the integrity of a three-dimensional heat-conducting network formed by the heat-conducting filler can be ensured to the greatest extent, and the heat-conducting coefficient of a product can be improved by about 1-3 times. In addition, the invention adopts a preparation method of direct hot-press molding after mixing, cancels a double-screw granulation process, obviously reduces energy consumption, raw material loss, labor expenditure and equipment expenditure in the production link, and greatly saves the cost.

Description

Preparation method of heat-conducting PVC (polyvinyl chloride)
Technical Field
The invention relates to the technical field of heat-conducting high polymer materials, in particular to a preparation method of heat-conducting PVC.
Background
As a general resin with large dosage, PVC has good mechanical property, but the heat conductivity coefficient of the conventional PVC product is only about 0.14-0.15W/MK, thus greatly limiting the application of the PVC in the fields of industrial heat exchange and electronics and electricity. At present, one of the most common and effective methods for improving the thermal conductivity of polymers is to fill the PVC with thermal conductive filler. However, in the actual working process, the heat-conducting polymer composite material is prepared in a melt blending manner, and due to the poor dispersibility and the influence of anisotropy of the heat-conducting filler, the heat conductivity coefficient of the heat-conducting polymer composite material cannot be expected by researchers; the heat-conducting polymer composite material prepared in a solution mixing mode has the problems of complex process flow, high preparation and recovery cost and low feasibility of large-scale industrial production.
Chinese patent CN201410548819.1 discloses a heat-conducting PVC composite material and a preparation method thereof, wherein the raw materials comprise PVC resin, heat-conducting filler, impact modifier, coupling agent, plasticizer, heat stabilizer and lubricant, and the heat-conducting PVC composite material is prepared by the processes of mixing, banburying and crushing, conical twin-screw extrusion granulation and the like, and has good heat-conducting property. However, the method has large raw material and energy consumption and high labor and equipment cost. Chinese patent application CN201710072773.4 discloses a high-strength PVC heat-conducting composite material and a preparation method thereof. However, in the method, the PVC powder which is only subjected to simple mechanical dispersion can have obvious thermal decomposition phenomenon in the hot-press forming process, and the forming effect is poor and the feasibility is low.
Disclosure of Invention
In order to effectively improve the heat-conducting property of the PVC composite material, simplify the preparation process, reduce the loss of raw materials and energy and save the labor cost and the equipment cost, the invention provides the preparation method of the heat-conducting PVC.
The invention provides a preparation method of heat-conducting PVC, which comprises the following steps:
(1) Adding a heat stabilizer and a plasticizer into the PVC raw material to prepare gelatinized PVC particles;
(2) Carrying out surface treatment on the heat-conducting filler by using a dispersing agent to obtain an active filler;
(3) Adding the active filler into the gelatinized PVC particles, and uniformly dispersing at 90-110 ℃ to obtain functionalized PVC powder coated with the active flaky filler on the surface;
(4) And (3) putting the functionalized PVC powder into a mold, and performing hot press molding.
Further, the preparation of the gelled PVC particles comprises:
(1) adding 2.5-4 parts of heat stabilizer into 100 parts of PVC raw material, and dispersing uniformly at high speed;
(2) adding 20-50 parts of plasticizer at 70 ℃, dispersing uniformly at a high speed, heating to 110-120 ℃, and keeping the temperature for 1-3 min under the stirring condition;
(3) cooling to 80-100 ℃, and preserving the heat for 30-60 min to ensure that the plasticizer is fully absorbed in the PVC particles to obtain the gelatinized PVC particles.
Further, the preparation step of the active filler comprises the following steps: preparing an aqueous dispersion containing 0.5-5% of a dispersant, adding the aqueous dispersion to the surface of the heat-conducting filler in the continuous stirring process in a spraying manner, fully and uniformly stirring, and drying; the mass of the dispersant is 1-5% of that of the heat-conducting filler.
Furthermore, the PVC raw material is general PVC resin, and the average polymerization degree of the PVC resin is 650-1400.
Further, the heat stabilizer is one of an organic tin stabilizer and a calcium-zinc composite stabilizer.
Further, the plasticizer is one or two of dioctyl phthalate, dibutyl phthalate, butyl benzyl phthalate, dioctyl terephthalate, acetyl tri-n-butyl citrate and trioctyl trimellitate.
Further, the heat conducting filler is one or two of graphene and hexagonal boron nitride.
Further, the dispersing agent is one of polyvinyl alcohol, polyvinylpyrrolidone and polyacrylamide.
Further, the hot-press molding is performed for 10-30 min under the conditions of 15-25 MPa and 140-180 ℃.
The invention has the beneficial effects that:
1. under the same formula condition, compared with the product prepared by the conventional processing technology (mixing, granulating, hot-pressing/injection molding), the heat-conducting PVC prepared by the method has the advantages that the heat-conducting filler is uniformly coated on the surface of PVC particles, the integrity of a three-dimensional heat-conducting network formed by the heat-conducting filler can be ensured to the greatest extent, the formation of a heat-conducting path is effectively promoted, and the heat-conducting coefficient of the product can be improved by about 1-3 times. Compared with the traditional banburying, extrusion and injection molding processes, the method can realize the preparation of the high-thermal-conductivity polymer material under the condition of lower content of the thermal-conductivity filler, and solve the problem that the system viscosity rises sharply along with the rise of the filler content in the traditional processing process.
2. The invention adopts a preparation method of direct hot-press molding after mixing, cancels a double-screw granulation process, greatly simplifies the process flow and can realize the application of the high-filling heat-conducting filler in the heat-conducting polymer composite material. Meanwhile, the energy consumption, the raw material loss, the labor expenditure and the equipment expenditure are obviously reduced in the production link, and the cost is greatly saved.
Drawings
In order to more clearly illustrate the embodiments or prior art solutions of the present invention, the drawings used in the description of the embodiments or prior art will be briefly described below, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.
FIG. 1 is a metallographic microscope photograph of general PVC pellets
Figure 2 is a metallographic micrograph of gelled PVC particles.
Fig. 3 is a metallographic microscope photograph of graphene coated gelled PVC particles.
Detailed Description
In order to make those skilled in the art better understand the technical solution of the present invention, the technical solution in the embodiment of the present invention will be clearly and completely described below with reference to the drawings in the embodiment of the present invention, and it is obvious that the described embodiment is only a part of the embodiment of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
Adding 2.5 parts of organic tin stabilizer into 100 parts of universal PVC with the average polymerization degree of 650, uniformly mixing, adding 20 parts of trioctyl trimellitate at 70 ℃, stirring, heating to 120 ℃, keeping the temperature for 1min, then cooling to 100 ℃, and keeping the temperature for 30min to obtain gelled PVC particles;
spraying 0.4 part of aqueous dispersion of polyvinyl alcohol (the concentration of the polyvinyl alcohol is 5%) into 8 parts of graphene, uniformly dispersing and drying, adding the graphene subjected to surface treatment into the gelatinized PVC particles, and uniformly dispersing to obtain functional PVC powder coated with active flaky fillers on the surface;
and (3) putting the functionalized PVC powder into a mold, and hot-pressing for 10min at the temperature of 180 ℃ under the pressure of 20MPa for molding.
Comparative example 1
The preparation method comprises the steps of dispersing 100 parts of universal PVC with the average polymerization degree of 650, 20 parts of trioctyl trimellitate, 2.5 parts of organic tin stabilizer, 8 parts of graphene and 0.4 part of polyvinyl alcohol uniformly at a high speed at 110 ℃, adding the mixture into a conical double-screw device, extruding and granulating at 155 ℃, banburying the granulated sample in a torque rheometer at 165 ℃, and then carrying out hot pressing at 15MPa and 180 ℃ for 10min for forming.
Example 2
Adding 4 parts of calcium-zinc composite stabilizer into 100 parts of general PVC with the average polymerization degree of 1400, uniformly mixing, adding 50 parts of dioctyl phthalate at 70 ℃, stirring, heating to 110 ℃, keeping the temperature for 3min, cooling to 80 ℃, and keeping the temperature for 60min to obtain gelled PVC particles;
spraying 0.1 part of polyacrylamide water dispersion (the concentration of polyacrylamide is 0.5%) into 10 parts of hexagonal boron nitride, uniformly dispersing and drying, adding the hexagonal boron nitride subjected to surface treatment into the gelled PVC particles, and uniformly dispersing to obtain functionalized PVC powder coated with an active flaky filler on the surface;
and (3) putting the functional PVC powder into a mould, and hot-pressing for 30min under the conditions of 25MPa and 150 ℃.
Comparative example 2
100 parts of general PVC with the average polymerization degree of 1400, 50 parts of dioctyl phthalate, 4 parts of calcium-zinc composite stabilizer, 10 parts of hexagonal boron nitride and 0.1 part of polyacrylamide are uniformly dispersed at a high speed at 100 ℃, added into a conical double-screw device, extruded and granulated at 145 ℃, added into an injection molding machine, and subjected to injection molding at 160 ℃.
The thermal conductivity of the above examples and comparative examples was tested according to ISO 22007-2-2008 with the following results:
TABLE 1 comparison of properties of thermally conductive PVC composites prepared by different methods
Item Thermal conductivity (W/(m.K))
Comparative example 1 0.427
Example 1 1.533
Comparative example 2 0.284
Example 2 0.593
As can be seen from table 1, on the premise of the same raw materials, compared with comparative examples 1 and 2 prepared by the conventional mixing, banburying crushing and conical twin-screw extrusion granulation processes, the heat conductivity of examples 1 and 2 prepared by the preparation method provided by the invention is improved by about 1-3 times.
Although the present invention has been described in detail by referring to the drawings in connection with the preferred embodiments, the present invention is not limited thereto. Various equivalent modifications or substitutions can be made on the embodiments of the present invention by those skilled in the art without departing from the spirit and scope of the present invention, and these modifications or substitutions are within the scope of the present invention/any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention.

Claims (9)

1. A method for preparing a thermally conductive PVC, comprising:
(1) Adding a heat stabilizer and a plasticizer into a PVC raw material to prepare gelatinized PVC particles;
(2) Carrying out surface treatment on the heat-conducting filler by using a dispersing agent to obtain an active filler;
(3) Adding the active filler into the gelatinized PVC particles, and uniformly dispersing at 90-110 ℃ to obtain functionalized PVC powder coated with the active flaky filler on the surface;
(4) And (3) putting the functionalized PVC powder into a mold, and performing hot press molding.
2. The method of preparing a thermally conductive PVC as claimed in claim 1, wherein said step of preparing gelled PVC particles comprises:
(1) adding 2.5-4 parts of heat stabilizer into 100 parts of PVC raw material, and dispersing uniformly at high speed;
(2) adding 20-50 parts of plasticizer at 70 ℃, dispersing uniformly at high speed, heating to 110-120 ℃, and keeping the temperature for 1-3 min under the stirring condition;
(3) cooling to 80-100 ℃, and preserving the heat for 30-60 min to ensure that the plasticizer is fully absorbed in the PVC particles to obtain the gelatinized PVC particles.
3. The method of preparing a thermally conductive PVC as claimed in claim 1, wherein the step of preparing the active filler comprises: preparing an aqueous dispersion containing 0.5-5% of a dispersant, adding the aqueous dispersion to the surface of the heat-conducting filler in the continuous stirring process, fully and uniformly stirring, and drying; the mass of the dispersant is 1-5% of that of the heat-conducting filler.
4. The method for preparing heat-conducting PVC according to claim 1, wherein the PVC raw material is general PVC resin with an average degree of polymerization of 650-1400.
5. The method for preparing heat-conducting PVC according to claim 1, wherein the heat stabilizer is one of an organotin stabilizer and a calcium-zinc composite stabilizer.
6. The method of claim 1, wherein the plasticizer is one or two of dioctyl phthalate, dibutyl phthalate, butyl benzyl phthalate, dioctyl terephthalate, acetyl tri-n-butyl citrate, and trioctyl trimellitate.
7. The method of claim 1, wherein the thermally conductive filler is one or both of graphene and hexagonal boron nitride.
8. The method of claim 1, wherein the dispersant is one of polyvinyl alcohol, polyvinyl pyrrolidone, and polyacrylamide.
9. The method for preparing heat-conducting PVC according to claim 1, wherein the hot-press molding is performed for 10-30 min under the conditions of 15-25 MPa and 140-180 ℃.
CN202210987518.3A 2022-08-17 2022-08-17 Preparation method of heat-conducting PVC (polyvinyl chloride) Active CN115433415B (en)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008189814A (en) * 2007-02-05 2008-08-21 Nitto Denko Corp Thermally conductive filler, method for producing the same, and method for producing resin molded article
US20140080954A1 (en) * 2012-09-19 2014-03-20 Chandrashekar Raman Methods for making thermally conductve compositions containing boron nitride
CN104327405A (en) * 2014-10-16 2015-02-04 广州合成材料研究院有限公司 Thermal conductive PVC composite material and preparation method thereof
US20180281244A1 (en) * 2017-03-30 2018-10-04 M-Victory Specific Material Co., Ltd. Manufacturing process of a solid thermal balancing composite material with lightweight
CN110423415A (en) * 2019-07-17 2019-11-08 鄂尔多斯市紫荆创新研究院 A kind of preparation method and masterbatch of graphene modified PVC composite material masterbatch

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008189814A (en) * 2007-02-05 2008-08-21 Nitto Denko Corp Thermally conductive filler, method for producing the same, and method for producing resin molded article
US20140080954A1 (en) * 2012-09-19 2014-03-20 Chandrashekar Raman Methods for making thermally conductve compositions containing boron nitride
CN104327405A (en) * 2014-10-16 2015-02-04 广州合成材料研究院有限公司 Thermal conductive PVC composite material and preparation method thereof
US20180281244A1 (en) * 2017-03-30 2018-10-04 M-Victory Specific Material Co., Ltd. Manufacturing process of a solid thermal balancing composite material with lightweight
CN110423415A (en) * 2019-07-17 2019-11-08 鄂尔多斯市紫荆创新研究院 A kind of preparation method and masterbatch of graphene modified PVC composite material masterbatch

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
沈芳等: "机械活化制备PVC/石墨导热复合板材的热性能", 塑料工业, vol. 42, no. 4, pages 111 - 115 *
赵笛等: "聚氯乙烯/石墨烯纳米复合材料的性能研究", 塑料工业, vol. 43, no. 5, pages 67 - 71 *

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